Automatic coal stoker



1943- R. KLOSSNER AUTOMATIC COAL STQKER Filed 001;. 9, 1939 3Sheets-Sheet 1 INVENTCR 3056 212 [X08522 e2 BY 1/ ATTORNEY R. KLOSSNERAUTOMATIC COAL STOKER Nov. 2, 1943.

3 Sheets-Sheet 3 INVENTOR Filed 001;. 9, 1939 ATTORNEY Patented Nov. 2,1943 UNITED STATES EPATENT OFFICE AUTOMATIC COAL STOKER Robert Klossner,Alliance, Ohio Application October 9, 1939, Serial No. 298,702

2 Claims.

This invention relates to improvements in automatic coal stokersespecially designed for household furnace use, and particularly tostokers of that type embodying a feed screw intermittently operated at alow rate of speed from an electric motor, or other relatively high speedmotor, continuously driven in one direction at a constant speed.

One object of the invention is to provide a stoker mechanism which maybe easily regulated as to feed speed, which is simple in constructionand composed of parts not liable to easily get out of order, which maybe manufactured and sold and kept in working order at a comparativelylow cost, and which allows easy and inexpensive replacement of thoseparts most subject to wear when occasion requires.

A further object of the invention is to provide a novel, reliable andefficient type of hydraulically operated transmission mechanism foractuating the feed screw from the electric motor or prime mover.

A still further object of the invention is to provide a transmissionmechanism of the type described which is wholly or largelyself-lubricating, and to provide a sectional construction of feed screwand other parts most liable to wear whereby these parts when worn may bereplaced in an easy, convenient and inexpensive manner.

With these and other objects in view, the invention consists of thefeatures of construction, combination and arrangement of parts,hereinafter fully described and claimed, reference being had to theaccompanying drawings, in which:

Fig. l is a perspective view of an automatic stoker embodying myinvention shown in connection with a furnace, with parts broken away andin section.

Fig. 2 is a vertical transverse section through the stoker casingshowing parts of the stoker mechanism in end elevation.

Fig. 3 is a perspective view of parts of the stoker mechanismdisassociated from the casing.

Fig. 4 is a perspective View of the valve block per se.

Fig. 5 is a sectional plan view on an enlarged scale through thehydraulic motor.

Fig. 6 is a view of the distributor valve.

Fig. '7 is a view of the reversing valve.

Fig. 8 is a perspective View of one of the sections of the feed screwshowing the construction thereof.

Fig. 9 is a sectional view through the pressure speed regulator.

Fig. 10 is a view showing a modification.

Fig. 11 is a vertical section on line ll-ll of Fig. 4.

Figs. 12 and 13 are detail vertical sections through the opposite endsof the pilot valve chamber, taken respectively on lines l2-|2 and l3-l3of Fig. 5, showing the ends of the valve as they appear in one of theoperative positions of the valve.

In the practical embodiment of my invention as herein disclosed, Idesignates a casing having an opening 2 in its top for the introductionof coal into a hopper 3' arranged therein, which opening may be normallykept close by means of a cover 4. The hopper 3 communicates at itsbottom with a feed conduit 5 in which is arranged to operate an auger orscrew conveyor 6 which is rotated in a manner hereinafter described tofeed the fuel to the bottom of a tuyere grate structure 1 arrangedwithin a heating furnace 8. The grate 1 herein shown is of the so-calledunder-fed type. The conduit 5 extends forwardly from the casing i aboveor alongside an air feed conduit 9 whereby air to promote and supportcombustion of the fuel is supplied to the grate, said conduit 9 havingarranged therein a suitable type of valve In to permit flow of air tothe grate and to prevent its return therefrom. In Fig. 1 thegratestructure I is shown as integral with the conduit 5, but, as shown inFig. 10, a replaceable elbow 5a may be arranged between the conduit andgrate to allow this part of the conduit, most subject to wear, to beeconomically renewed whenever required.

The auger or screw 6 comprises a suitably journaled shaft II on whichthe screw proper 6 is mounted. This screw proper comprises a series ofsections l2 each longitudinally bored axially to receive the shaft andpermit slidable fitting of each auger section on or its removal from theshaft. The series of auger sections may be retained on the shaft againstdisplacement by holding means of any suitable type to prevent theirlongitudinal displacement while permitting of their removal whenrequired. The meeting faces of adjacent auger sections are constructedto interfit, or they are provided with clutch surfaces l3 forinterengagement with each other to hold the sections coupled together.The construction described provides for the ready removal of any portionof the conveyor screw which may become unduly worn or damaged in serviceand its replacement by a new section without the necessity of the ownerof the stoker being compelled to buy a new fully renewal screw. Inpractice, the shaft may be made of angular shape in crosssection and thebores of the auger section correspondingly shaped so as to adapt thesections to be held against independent rotation on the shaft and torotate positively with the shaft as the latter is operated.

A part of the casing I is interiorly partitioned to provide a fan orblower chamber I4 communicating with the air duct 9 and a transmissionhousing or chamber I5 separate from said fan or blower chamber, andwhich chamber I5 is suitably formed or constructed to provide at itsbase a reservoir for a storage of a body of oil I6. The outer end of theshaft II extends into the chamber I5 and has mounted thereon a disk orhead I! enclosed within or encircled byv the annular body portion I8 ofan oscillator I9 having a motion transmitting arm projectingtherefrom.The outer peripheral surface of the disk I! and the inner peripheralsurface of the annular body I8 are formed with pockets havingabutmentshoulders and inclined surfaces and receiving ball or roller members 2|forming a ball or roller typeof ratchet connection between the shaft andoscillator whereby intermittent or step by step rotation may be impartedto the shaft I I to drive the conveyor 6 on its speed motion. It will beobvious that in one direction of motion the oscillator through theratchet connection will impart a partial rotation to the shaft in onedirection, and that in itsother direction of motionthe ratchetconnection will permit the oscillator to move in the reversedirectionwithout operating the shaft. The elements I1 and I9 constituteparts ofa. hydraulic transmission mechanism. for imparting from a drivemotor, revolving constantly in a single direction at. a relatively highspeed, an intermittent or step bystep rotation tothe screw conveyor 6which is rotatable inits feeding operation at a much lower rate ofspeed.

The electric motor or prime mover 22 employed for driving the feed screwthrough suchitrans mission mechanism may be of a conventional standardspeedlphase and constant speed type. This motor22-bymeans, of a belt 23or othertype of gearing drives; a, shaft 24 suitably journaled withimthecasing The shaft 24 in turn operates a blower-orfan 25;wh-ich suppliesair to the conduit-9 and also operatestheimpeller of a rotary; oil pump,26 which communicates with an oil lfeedortsupplypipe 2Iwhich dips downinto the body of .oil I6,in.the oil reservoir. The oil so taken up bythe pump is forced through a deliverypipeZfl, topthe feed valvemechanism of a; hydraulic motor, generally designated 29, which operatesthe oscillator I9. The oil on its flow; to the vpipe ,2 8 frorn the pump26 passes through a pressurespeed regulator of suitable type, and whichmay include a regulating or throttle valve 3I,- whereby thevolume; andworking pressure of theoil, delivered to the pipe 28 may be regulatedand controlled.to ;govern the action of the hydraulic motor and thespeed of the oscillator I9 and consequently the speed of. rotation ofthe feed.- .screw- 6.

The hydraulic motor29 comprises a .central valveblock or casing 32 atopposite ends of which are arranged cylinders 33 and 34, which parts arebolted together or otherwise suitably united. In the. cylinder 33operates a load piston and in. the cylinder 34 operates a reverseorreturn piston 35,. These pistons are of single acting type piston35operating on its inward movement to transmit a working, motion to theoscillator I9,andpiston. 36.operating on its inwardlmpve:

ment to transmit an idling or return motion to the oscillator. A rod 31couples the pistons for movement in unison and this rod is suitablycoupled to the arm 20 to transmit motion to the oscillator.

In the valve block or casing 32 are formed a manifold chamber 38 havingan intake port 39 connecting with pipe 28, a distributor valve chamber40 and a pilot or reversing valve chamber M, in which chambers 40 and 4I are arranged sliding distributor and pilot valves 42' and 43.Connecting chambers 40 and 38 are feed ports 55 and 44', and connectingchamber 40 with the outer ends of the respective cylinders are feed andreturn passages 45 and 45, between which lies an exhaust passage 43 forthe return of oil from the cylinders and chamber 40 back to the oilreservoir; In addition to the aforesaid ports and passages the valvecasing is provided with passages 47 and 41' connecting opposite ends ofthe manifold chamber 38 with opposite-endsof the pilotyalve chamber4'I', passages 48 and 48 connecting opposite. ends of the distributorvalve chamber 40 with the ends of the pilot valve chamber 4!, andventports 4821, 4817' for cooperationwith passages 48, 48,;

The distributorvalve. 42 is provided'with siniilar annular endenlargements or heads 49 which always close communication between theends of the chamber. 40 and thep'orts 44,.4'4", 45and45. Between theseenlarged endportionsor heads 49 the valve is provided :withapair ofspaced heads 5!], 50' forming betweenthemannular'ports 5|, 52and 53,whichheads 5B ,andifll and ports 5|, 52 and 53 control communicationbetween the center ports 44, ,45 and 44-,.45' and theportsfi and 45 andport 46. The pilot\ va1ve.43is pro videdadjacent itsrendszwith. annularports 54 and 55 for. cooperation respectively with thesets ofports 41.and =48-and 4'I' and-48% The valve 43 is also providedwith reduced endextensions or abutments 56 and 56' which project through end walls ofthe. valvecasing into the respective cylinders 33 and 34-fo1wthecontact-therewith of the pistons '35 and 35110 shift .theyalve 43 inopposite directions fcr effectinga reversing operation of the valve 43.These reduced ends 55. 56' of valve 43- also provide for the exhaust ot-oil through ports.-48, 48" and the vent ports- 4841,4819 from chamberr 4 I in the reversing movements of the valve 43. The valve 43 isgfurther proyidedbetween the-resDfiGtive ports :54 and. 55 andtherespective end extensionsi5fi=and 56 with heads 54 and 55. tocontrolcommunication :between the ports 41, 48,41, 48",'-,48a. and-48b,-as hereinafter described. It'W l1rbQ nd X W0d" ha inpractice theelectric motor 22 .is:driven-constantly? in one direction and operatesthe shaft 24 whichidrives the fan 25 tocontinuously supplyair tothejfurnace grate, the shaft -24valso driving the-pump 26 to supply oilfromthe oil reservoir to'the valve chamber for controlling theworkingopervations of Ithe;p istons 3,5,; and :36. 'I'hrough the mediumof the regulatonor speed controlleddevice the amount of oil supplied tothe-valve chamber and itspressure may be regulated 5 to control thespeedof ope-ration ot.- the hydraulic motor, any excess oilnot allowed:topass bythe regulatorv being returned to the-oil reservoir. The supplyof OlIfIEOm'thG pump to the controlling valves and: cylinderseffectsfirst a working motion of the oscillator in one direction-andthen a.return..motion of the-.osc.illator or its movement in theopposite direction, the oscillator in its working movement transmitting(motion in its clutch connection to the feed screw for a coal feedaction and on its reverse or return motion acting idly or without motiontransmitting efi'ect on the feed screw. The hydraulic motor through theaction of the oscillator will actuate the feed screw intermittently at aslow rate of speed, while the motor continues to operate at a uniformlyhigh speed, so that a step by step feed action of the screw on the coalis obtained. In the operation of the pump, hydraulic motor and motiontransmitting mechanism, these parts are properly lubricated from the oilor motive fluid supplied from the reservoir, thus reducing the number ofparts which have to be lubricated, and if desired the remaining parts ofthe apparatus may be lubricated by automatic means of suitable type fromthe same source. Thus those portions of the apparatus with the exceptionof the feed screw which are the most subject to wear will operate for along period and, as the use of a valve mechanism of the type describedobviates the employment of packings or the like, the liability ofderangement of the valve mechanism and the necessity of making repairsthereof will be reduced to the minimum. As speed reduction is obtainedwith my device without the use of planetary gears, internal pumps andthe like, and as no springs are used which are liable to break or becomeineflicient, the construction of the apparatus as a whole isconsiderably simplified, so that it may be manufactured and sold andkept in working order at a comparatively low cost.

Fig. 5 discloses the parts of the hydraulic motor as they appear whenthe oscillator and load piston are at the limits of their returnmovements and about to make a power stroke, In this position of theparts the valve 42 has been moved to the right by oil pressure supp-liedthrough ports and passages 41, 54 and 48 so as to establishcommunication through passages 44 and 45 between the manifold andcylinder 33 and to establish communication between the exhaust port 45and the passage 45' with the cylinder 34. In this position of the partsthe reversing valve 43 is at the limit of its left hand movement, towhich it has been shifted by the previous inward movement of the piston36, so that its port 54 connects the passages 4'! and 48 and its head 54closes vent port 48a, while its port 55 lies out of alinement withpassages 47' and 48 while its head is in position to close passage 4?and open communication between passages 43, 43b to allow oil to exhaustfrom 48' over reduced projection 56 and out through port 43b, as shownin Fig. 13, so valve 42 can shift. The projection 56 in this position ofvalve 43 extends into cylinder 33 so as to lie in the path of inwardmovement of the piston 35. Fluid pressure thus being supplied to theouter end of the cylinder 33 the piston 35 is moved inward on itsworking stroke and actuates the oscillator on its Working stroke, piston36 at the same time being moved outward in its cylinder 34 to force theoil contained therein outward through the exhaust port 46 back to theoil reservoir. When the piston 35 reaches the limit of its inwardmovement it engages projection 55 of valve 43 and shifts said valve toits right hand end position in which its passage 54 is moved out ofalinement with ports 47 and 48 and its passage 55 connects ports 41 and48, whereby fluid under pressure is supplied to the right hand end ofthe valve chamber 40 to shift the valve 42 to its left hand position inwhich it establishes communication between ports 44 and 45' for flow ofoil to the outer end of the cylinder 34 and closes communication betweenports 44 and 45, While at the same time opening communication betweenports 45 and 43 so as to allow exhaust of oil from the cylinder 33 backto the oil reservoir. In such movement of valve 43 its head 54 moves toa position to close port 41 and establish communication between ports48, 48a to allow oil to exhaust from 48 over projection 56 and outthrough port 48a, as shown in Fig. 12,. to permit valve 42 to shift toits left hand position. Action of the oil under pressure admitted tocylinder 34 forces the piston 35 inwardly so that the piston 35 will bemoved backward to the outer end of its cylinder 33 and so that theoscillatorwill be moved idly back to its initial position ready foranother power stroke. The power stroke movement of the piston 35 whichshifts the valve 43 to its right hand end position projects its endportion 53 into the cylinder 34, so that when the piston 35 reaches itsinward movement it engages the extension 53 and shifts the valve 43 backto its left hand working position for a repetition of the power strokeaction of piston 35 previously described. It will be apparent that inthese operations great ease of motion of the pistons and valve elementswill be obtained so that the working parts will operate in a practicallynoiseless manner.

The pressure speed regulator 33 may be of any preferred type ofconstruction. As shown in the present instance it comprises a valvecasing 51 connected with the outlet or delivery pipe 58 leading from thepump, and which is arranged between said pipe 53 and the delivery pipe28 leading to the feed valve mechanism of the hydraulic motor. In thiscasing 51 is arranged the. throttling valve 3| which is adjustable bymeans. of an operating handle 3| to cause a port 59 in said valve toregister to a greater or less extent with the pipes 23 and 53, wherebythe flow of oil from the pump to the hydraulic motor may be controlledby a throttling action to regulate its volume of flow and workingpressure as desired. Communicating with the pipe 58 between the casing5'! and the pump is a relief valve chamber 59 having a passage 3|communicating with the pipe 53 and controlled by a valve 62 normallyheld closed by a spring 53 adapting it to open at a predeterminedpressure to provide for the escape of excess oil through an overflow ordrain pipe 54 back to the intake of the pump or to the oil reservoir.The spring 53 is disposed between the valve 62 and a threaded plug 65which is adjustable to enable the pressure of the spring 63 to beregulated and which is adapted to be locked in adjusted position by alock nut 66.

What I claim is:

1. In a motion transmitting apparatus, a hydraulic motor embodyingopposed spaced working and return cylinders and a valve casing betweensaid cylinders, said valve casing having a manifold chamber, a pilotvalve chamber opening at its ends into the cylinders, a reversing valvechamber, fluid feed ports connecting the manifold chamber with the endsof the pilot valve chamber, feed ports connecting the manifold chamberwith the reversing valve chamber, fluid feed and vent ports connectingthe ends of the pilot valve chamber with the ends of the reversing valvechamber, fluid supply and return ports connecting the reversing Valvechamber with the outer ends of the cylinders, and a fluid exhaust portleading outwardly from the reversing valve chamber, load and returnpistons respectively operating in said cylinders, means coupling saidpistons for movements in nison, a reciprocatory reversing vvalve in saidreversing valve chamber shiftable in opposite directions for alternatelycontrolling the flow of, fluid fromthc second-named feed ports through,the supply an return ports to and from the respectivecylinders and itsexhaust from the cylinders, through the exhaust port, and areciprocatory pilot valvein said pilot valve chamber having opnositeendpore tions exposed in the cylinders so as-to be alter-c nately engagedby the respectivepistons for shift, ing the valve in oppositedirections, said pilot, valve having end portions governing the first,-named feed ports and the said fluid feed and vent ports to alternatelycontrol the feed. of fluidl tor the opposite ends of the reversing valvechamber and its exhaust therefrom.

2. In a motion transmitting apparatus, a. hy-. draulic motor embodyingopposed spaced Work ing and return cylinders andv a valve casing:between said cylinders, saidvalve casing having, a manifold chamber, apilot valve chamber opening at its ends into the cylinders, a re?versing valve chamber, fluid feedrportsconneoting the manifold chamberwith the ends of the pilot, valve chamber, feed portsconnecting themanfn. fold chamber with the reversing valve chamber,

fluid feed and vent portsconnecting the .endsof,

the pilot chamber with the endsof the reversing valvechamber, fluidsupply and return ports con necting the reversing valve chamber with theouter ends of the cylinders, and a fluid port leading outwardly irom thereversing valve chamber, load and return pistons respectively operatingin, said cylinders, a reciprocatory re,- versing valve in the reversingvalve chamber come prising, a, cylindrical valve body shiftablelongitudinally in said chamber ,andvlhaving heads a e, interveninggrooves governing the second-named. Iced ports, the supply and returnports and'the exhaust port for alternately controlling theflow oi fluidfrom said second-named reed port's through, the supply and return portstoand from r the respective cylind'ersandits exhaust from the:

cylinders through the exhaust port, and, a recip-. rocatory pilot valvein the pilot valve chamber comprisinga cylindrical. valve bodylongitudinally shiftable in, said chamber and having'opposite end,portions exposed in the cylinders so astuber engaged by the pistons toalternately the. valve in, opposite directions, said va lve. having,end? portions provided, with; heads and mtervening, grooves governing.the first-named feed portsandi thesaidfiuidfeedand vent ports onits-opposite.- shifting movements to alternatelygcontrol: the feed of.fluid to the opposite BIIdSFOf' the reversing valve. chamber and itsexhaust therefrom.

ROBERT KLOSSNER.

